It depends on the situation and the people involved. There are some cases when a certain amount of distance is needed, be it because of the leader/boss or the people under them. That said, it should never get to the point of being so distant and impersonal that it's like working for a stranger.

To a certain extent this is OK, but only eg a police officer to the accused. This doesn't work well in a working or even teaching relationship. I used to hate it at TAFE when I would be nice to a lecturer and I could sense they were purposely keeping their distance. I get insulted when people do that all because they are trying to keep their 'professional front.' I mean what is their problem? Are they afraid I'll ask them out on a date? If you want to build trust and rapport, this is not the way to go. A good working or learning enviornment is a freindly enviornment.